首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3979篇
  免费   237篇
  国内免费   43篇
耳鼻咽喉   66篇
儿科学   133篇
妇产科学   140篇
基础医学   421篇
口腔科学   109篇
临床医学   396篇
内科学   729篇
皮肤病学   52篇
神经病学   199篇
特种医学   229篇
外科学   768篇
综合类   96篇
预防医学   300篇
眼科学   139篇
药学   202篇
中国医学   29篇
肿瘤学   251篇
  2022年   46篇
  2021年   78篇
  2020年   58篇
  2019年   74篇
  2018年   111篇
  2017年   78篇
  2016年   69篇
  2015年   73篇
  2014年   126篇
  2013年   156篇
  2012年   224篇
  2011年   217篇
  2010年   140篇
  2009年   143篇
  2008年   158篇
  2007年   186篇
  2006年   159篇
  2005年   159篇
  2004年   158篇
  2003年   135篇
  2002年   142篇
  2001年   122篇
  2000年   137篇
  1999年   117篇
  1998年   62篇
  1997年   50篇
  1996年   42篇
  1995年   30篇
  1994年   46篇
  1993年   35篇
  1992年   67篇
  1991年   76篇
  1990年   53篇
  1989年   52篇
  1988年   61篇
  1987年   55篇
  1986年   72篇
  1985年   57篇
  1984年   29篇
  1983年   29篇
  1982年   16篇
  1980年   20篇
  1979年   25篇
  1978年   20篇
  1976年   26篇
  1974年   26篇
  1973年   24篇
  1972年   18篇
  1970年   14篇
  1969年   15篇
排序方式: 共有4259条查询结果,搜索用时 250 毫秒
1.
This study qualitatively examined factors that influenced contraceptive choices in a sample of young, HIV-infected women. Individual qualitative interviews were conducted among 30 vertically and horizontally HIV-infected women (= 26 African American) from the ages of 14 to 24 years (Mean age = 20.9 years). We recruited sample groups with the following characteristics: (a) current contraceptive/condom use with ≥1 child (= 11); (b) current contraceptive/condom use with no children (= 12); and (c) no current contraceptive/condom use with no children (= 7). A semi-structured interview guide was used to ask participants about factors influencing past and current contraceptive choices. Individual interviews were digitally recorded and transcribed verbatim; analyses to identify core themes were informed by the Grounded Theoretical approach. Young, HIV-infected women did not identify their HIV serostatus or disease-related concerns as influential in their contraceptive decisions. However, they reported that recommendations from health-care providers and input from family and friends influenced their contraceptive choices. They also considered a particular method’s advantages (e.g., menstrual cycle improvements) and disadvantages (e.g., increased pill burden) when selecting a method. Findings suggested that HIV-infected young women’s contraceptive decisions were influenced by factors other than those related to their infection.  相似文献   
2.
We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.  相似文献   
3.
Post-traumatic retinal detachment occurs frequently as a late consequence of progressive vitreous changes, especially following penetrating injuries. Occasionally, it develops soon after the trauma, without preceding proliferative vitreoretinopathy, is based on posterior vitreous detachment and morphologically resembles an idiopathic retinal detachment. It is possible that the posterior vitreous detachment in these cases is encouraged by the presence of intravitreal hemorrhage.  相似文献   
4.
5.
6.
We reviewed 134 primary noncemented porous-coated total hip replacements in 125 patients: 64 were DePuy AML prostheses, 20 were Howmedica PCA and 50 were Implant Technology LSF. The prostheses had been in situ for an average of 36 months, 40 months and 24 months respectively. The average pre-operative Harris hip scores were 38.2 for AML, 33.2 for PCA, and 41.0 for the LSF prostheses. The average postoperative scores were 80.7 for AML, 83.8 for the PCA, and 91.5 for LSF. Thigh or groin pain associated with the prosthesis was present in 30% of AML, 30% PCA and 8% of the LSF cases. The clinical and radiographic review showed better early results with the LSF prostheses than the others; this seemed to be related to the implant design, which provided improved initial stability and more physiological transfer of load.  相似文献   
7.
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC.  相似文献   
8.
9.
Knee anterior cruciate ligament reconstructive surgery has significantly evolved and now includes the option of using an allograft. This has resulted in numerous studies evaluating the advantages and disadvantages of allografts. The purpose of this literature review is to evaluate this research and present important findings to allow the selection of the most appropriate graft source when considering allograft versus autograft reconstruction.  相似文献   
10.
The authors report a spiny dogfish (Squalus cubensis/megalops group) sting of a professional fisherman. He was injured on the left hand by the spine anterior to the fish's dorsal fin and manifested local edema, erythema, and excruciating pain for 6 h. Sharks of the genus Squalus megalops/cubensis and Squalus acanthias are found throughout the world; they have two spines in front of their dorsal fins and channels with a whitish mass containing large vacuolated cells which secrete venom. The Squalus genus has a complex taxonomy; the species involved in this injury belongs to the megalops/cubensis group. A detailed taxonomic and toxinological study on the Squalus genus is important and would complement other work on these fish, especially as stings in humans are very rare and not fully understood.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号